Simultaneous Multiresolution Imaging Based on Multimode MIMO-SAR

Abstract

This article proposes a novel imaging mode which allows for the acquisition of SAR images with different resolution in a single imaging process, specifically designed for multiple-input–multiple-output synthetic aperture radar (MIMO-SAR). To achieve this, a multimode array system model based on 2-D intrapulse scanning is established, followed by the division of full aperture signals into subaperture signals. Improved azimuth phase coding (APC) technology is then employed to separate multimode echo signals, and spatial filtering technology and range digital beam forming technology are used to remove ambiguity in azimuth and range of the subaperture signals of each mode. Finally, subaperture image coherent fusion algorithm is used to generate high-resolution images corresponding to the full aperture of each mode. Simulation results show that the improved APC can effectively separate multimode echo signals, and the multiresolution characteristics and imaging effect are verified.

Keywords

• Azimuth phase coding (APC)
• multimode
• multiple-input–multiple-output synthetic aperture radar (MIMO-SAR)
• multiresolution
• subaperture